叶顶抽吸对叶栅间隙泄漏流动的控制研究

Effects of Blade Tip Suction on Cascade Gap Leakage Flow

关键词:  叶顶抽吸  端壁抽吸  叶尖泄漏流  泄漏涡  流动控制技术

Key words:  Blade tip suction  Endwall suction  Tip leakage flow  Leakage vortex  Flow control technique

摘要:

为了控制压气机叶尖间隙泄漏流动，减少叶尖泄漏流和泄漏涡对压气机内部流场带来的不利影响，数值模拟研究了在压气机叶栅叶顶位置沿叶片中弧线开槽抽吸对叶尖泄漏流的控制效果，并与端壁流向开槽抽吸方案进行了对比分析。研究结果表明：叶顶抽吸和端壁抽吸直接通过影响叶尖泄漏流的结构形态，减弱间隙泄漏流强度和影响范围，从而提升压气机/叶栅性能。叶顶中游抽吸方案Slot TB对于泄漏流与泄漏涡的控制效果优于叶顶上游抽吸方案Slot TA；而机匣端壁上游抽吸方案Slot CA相较于中游抽吸方案Slot CB对叶顶流场改善效果更佳。叶顶抽吸和端壁抽吸在抽吸量为0.6%时分别可以使总压损失系数下降约3.3%和7.2%。

Abstract:

In order to control the tip leakage flow, and reduce the adverse effects of tip leakage flow and tip leakage vortex on the internal flow field of compressors, the flow control effects of opening suction slots along the direction of the blade tip camber on the tip leakage flow in a compressor cascade were numerically studied. Moreover, a comparative analysis was performed with the endwall suction schemes that slotted in flow direction. The results show that the blade tip suction and endwall suction can weaken the intensity and range of tip leakage flow by directly affecting the structure of the tip leakage flow, thus improve the performance of compressor or cascade. The blade tip midstream suction scheme Slot TB has a better flow control effect on the tip leakage flow and tip leakage vortex than that of the blade tip upstream suction scheme Slot TA. However, the endwall upstream suction scheme Slot CA has a better effect on modifying the tip flow field than that of the endwall midstream suction scheme Slot CB. The total pressure loss coefficients were reduced by 3.3% and 7.2% when the suction amount was 0.6% with the blade tip suction and endwall suction, respectively.